1. Field of the Invention
The present invention relates to a hardness tester and to a hardness testing method.
2. Description of Related Art
A conventional hardness tester is known which measures hardness of a sample based on dimensions of an indentation formed by pressing an indenter against the sample (work piece) with a predetermined test force. For example, a Vickers hardness tester measures a length of diagonal lines of an indentation formed by pressing a quadrangular pyramidal indenter into a surface of the sample, and calculates hardness based on the measured length of the diagonal lines of the indentation (see, for example, Japanese Patent Laid-open Publication No. 2012-78306).
In recent years, in cases where a plurality of samples having an identical shape are repeatedly measured using the above hardness tester, a “parts manager” has been used. A parts manager is a function used when repeatedly executing a program of a test pattern laid out for one sample (a parts program) on another sample having an identical shape. For example, a parts manager settings screen G2 shown in FIG. 10 includes a parts count definer 201 defining a number of samples having an identical shape arranged in each of a column direction and a row direction; and an interval definer 202 defining an interval between samples adjacent in the column direction and an interval between samples adjacent in the row direction. By defining the number of samples present in each of the column and row directions as well as the intervals between adjacent samples in the column and row directions on the parts manager settings screen G2, an identical test pattern can be defined for a plurality of samples. As shown in FIG. 11, in a case where the orientations and intervals, for example, of the samples S are regular, defining a test pattern for the plurality of samples can be facilitated by using the parts manager.
However, in a case where the orientations and intervals of the samples are not regular, the test pattern cannot be easily defined with the parts manager settings screen G2 shown in FIG. 10. Instead, after defining the test pattern, an extensive recovery process is required of a user, such as correcting the position and direction of each sample. Even when the orientations and intervals of the samples are made regular using a jig, for example, a sample may slip out of arrangement, or the number of samples may differ at the time the parts program is recorded and the time the parts program is executed. In such cases, when the parts program is executed according to the number of samples defined at the time the parts program is recorded, a measurement error may occur at measurement locations where no sample is present. Accordingly, a separate operation is required to instruct that a measurement be omitted, negatively affecting operability.